WMC Important question for GTU

1. Explain the Benefits of Wireless communication /Advantages of Wireless communication.
2. Explain the Security threats of wireless communication and safeguard measures that can be taken to minimize them. 
3. List all the disadvantages of the Wireless Networking / Concerns of wireless networks/ issues of wireless networking.
4. Explain physical components used to form Wireless network.
5. Explain logical Architecture of the wireless network.
6. Explain the Different Types of infrared light LAN.
7. Short note: Interference / types of interference/ Inward & Outward interferences.
8. Explain advantages and disadvantages of Radio based wireless LAN.
9. Types of Antenna.
10. Components of WIN.
11. Differentiate between Spread Spectrum and Direct Spread Spectrum Modulation.
12. Compare Narrow band Modulation and Spread Spectrum Modulation.
13. Explain Following Terms:

Types of Antenna, Mobile ware – is software that enables u to communicate over cellular or regular wire line phones.

14. Explain Multiple Cell Wireless LANS. Compare it with Single-Cell Wireless LANS.
15. Different types of wireless LAN.
16. How does Roaming works? Explain all the attributes that affect it.
17. Differentiate between FHSS & DSSS working.
18. What is spread spectrum modulation?
19. Explain Radio based wireless LAN configurations in detail.
20. Explain CDPD Standard in detail / Explain Goals & Objectives of CDPD network & its Architecture.
21. Differentiate between local and remote bridges in wireless communication network.
22. Different modes of wireless LAN.
23. Explain Packet Radio WAN Architecture & its components / Explain Packet. Radio WAN Architecture & Packet Radio Operations.
24. What are the services provided by ‘ARDIS’-A Packet Radio Service Provider.

25.  Explain SkyTel’s Two way paging Network.

26.  802.11 frame format.

27.  Types of Wireless LANs.

28.  Compare: Wireless LAN and Wireless WAN.

29. Explain Two-Way-Pager Networks with its pros and cons.

30.  Explain LEO & GEO satellites.

31.  MAC protocols for satellite links.

32.  Explain: Hybrid networks.

33. Analog Cellular Technology.
34. Discuss the components of any satellite system/ List all main components of satellite system & their importance in system.
35. Explain GSM Network Architecture and show call path routing in GSM.
36. Explain: GSM interfaces.
37. Explain different call flaw sequences in GSM.
38. Short note: GPS.
39. Explain the automatic vehicle locating GPS System – ‘Mobile Trak’
40. How GPRS functionality does get activated over GSM networks?             
41. Explain GPRS network Architecture.                                                                       
42. Data routing in GPRS.
43. Features of GPRS.
44. Limitations of GPRS network.
45. Explain: GPRS interfaces.                                        
46. Explain WAP Architecture in detail / WAP Components.
47. Short note : WAE
48. Explain the ways to handle the database consistency issue when the database is accessed through WAP Architecture.
49. Explain WTP classes of WAP Architecture in brief.
50. Short note: “WAP Programming Model”.
51. Explain WAP Protocol Stack in detail.
52. Explain the usage of following WML tags along with the parameters.

<a> <anchor> <card> <do> <go> <fieldset> <img> <input> <setvar> <Template> <Postfiled> <Meta> <smail> <br> <anchor> <table> <timer> <spawn>

53. Write WML Script that will ask username and password. Display appropriate message depending on the input mode by the user / Write a program in WML to check inputted username and password and display appropriate message. Take hardcode password and username. Give proper validation checks.
54. Write a WML Script to perform all major functions of a standard calculator.
55. Write WML Script for a Shopping Complex, where use will select items to be brought and specify its quantity. From the already existing database, it should read the amount of all the items and generate bill.
56. Explain: Lang Library.
57. Explain the following WMLS library functions:

Ceil, abort, seed, squeeze.

58. Write a program to store the marks of all the students of the class for all semesters in the database. Display them rank wise. Also provide the searching facility on the name of student.

59. Define following Terms

Agent Discovery, Registration, Tunneling, Home Agent, Case-of Address Collocated address, foreign agent, Deregistration, WAE, Agent Solicitation, Mobile Security Association, Rollover handling, ICMP, Handover, Home Agent Discovery, Localization.

60. Explain Mobile IP registration procedure.
61. Explain different message format for the registration process of mobile IP. / Explain Registration Reply packet format in detail / Explain Registration Request Packet format in detail.
62. Explain two level addressing schemes in terms of IP addressing.
63. What do you understand by tunneling? Why tunneling is required for mobile communication systems? / Short note: Tunneling.
64. Differentiate between solicitation and advertisement techniques of mobile computing.
65. Explain sequence number and roll over handling methods in terms of agent advertisement.
66. Explain two tables maintained by the foreign agent during registration.
67. List the reasons to get registration denial from foreign agent.
68. How and when Mobile node discovers an agent?
69. Explain Agent Discovery & its various extensions.
70. Short note: Deregistration /Explain Deregistration by mobile nodes along with message format.
71. Explain Abstract Mobility Management Model. Also list the functions required to support mobility / Explain IETF Mobile IP Abstract Model in detail.
72. What is validity check? Explain various validity checks with registration replies.
73. Discuss source routing? Compare it with Tunneling.
74. Explain Registration with a collocated care-of address using appropriate Example.
75. Explain when following codes will be used for denied by foreign agent/home agent: 69, 73, and 88,131,136.
76. Discuss how mobile node determines that it had moved in detail.
77. Explain how a mobile node can learn the address of a home agent in detail.
78. What Protocols are used in tunneling?
79. Middleware.
80. Explain TCP timers in Mobile Network.
81. Explain TLV format in detail.          
82. Explain Router Discovery Protocols.
83. Explain how Van Jacobson Compression works in detail.
84. Describe the processing done by home agent for registration of mobile node.
85. Discuss message format for the router advertisement messages.
86. Explain ICMP message for router discovers.
87. Explain Columbia mobile IP abstract model / explain the architecture of Columbia Mobile IP in detail.
88. Explain the basic working of Mobile IP. How does it take care of mobility of user? Explain operation of Mobile IP protocol.
89. Differentiate: Mobile IP and CDPD.
90. Enlist the products/items that can provide mobility. If mobile IP is not existent.
91. Explain Dynamic Source routing in Ad-hoc Networks.
92. Why Ad-hoc network has been the special treatment as in compared to any other wireless network?
93. IEEE 802.11 standard.
94. Describe steps of mobile communication.
95. Explain Following Terms:

Paging, Constellation, Frequency Reuse, routing, Handover, Cell, ICMP, Collocated care-of address

96. State whether true or false:
1. WML is not a case-sensitive language.
2. MAX_SOLICITATION tells about the speed of the router, with which it can send advertisements.
3. F and H bits of Agent Advertisement can’t be simultaneously.
4. Identification number is used to identify proper mobile node for which this request.
5. A mobile node can only be registered to a single agent as foreign node at any moment if time.
6. Relay node routing table in Packet radio contains an entry for each possible destination nodes in that WAN.
7. CDPD provides half-duplex communication.
97. What are different types of cells and why are they required?
98. Limitations of 2G Mobile Devices.
99. Explain various wireless multiple access methods / multiple access technology.
100. Discuss various cell splitting technologies. Why at all cell splitting is done?
101. Explain passive reception of wireless network data in detail.
102. Explain the evolution of 3G technologies as compared to that of previous generations.
103. How mobility is managed in Cellular technology?
104. Discuss some basic components required in any basic cellular architecture with their functionalities viz. HLR, etc.

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Voice over Internet Protocol (VoIP)

Ø Technology to enable voice communication over the IP network became known as Voice over Internet Protocol or VoIP, in short.

Ø Today, there are two sets of standards for VoIP switching, media, and gateways. These are H.323 from International Telecommunications Union (ITU) and Session Initiation Protocol (SIP) from Internet Engineering task Force (IETF).

 v H.323 in VoIP – MCU

Ø The Multipoint Control Unit (MCU) supports conferences between three or more endpoints. An MCU consists of a Multipoint Controller (MC) and a Multipoint Processor (MP).

Ø The MC handles H.245 negotiations between all terminals to determine common capabilities for audio and video processing. An MCU optionally may have one or more MPs to deal with the media streams.

Ø MP mixes, switches, and processes audio, video, and/or data bits.

v SIP in VoIP

Ø The Session Initiation Protocol (SIP) is a signaling protocol fortelephone calls over IP. SIP is defined by the IETF and is gaining popularity.

Ø Unlike the H.323, SIP is designed specifically for the Internet.

Ø SIP defines interfaces for establishing, modifying and terminating sessions with one or more participants in the VoIP environment. It facilitates development of telephony application.

Ø SIP supports the following facets of establishing and terminating multimedia communications: User location; User capabilities; User availability; Call setup; Call handling, and Call teardown.

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GPRS introducation

Ø General Packet Radio Service

Ø Step to efficiently transport high-speed data over the current GSM and TDMA-based wireless network infrastructures

Ø Deployment of GPRS networks allows a variety of new applications ranging from mobile e-commerce to mobile corporate VPN access

Ø GPRS allows for data speeds of 14.4 KBps to 171.2 KBps, which allow for comfortable Internet access

Ø Allows for short ‘bursty’ traffic, such as e-mail and web browsing, as well as large volumes of data

Ø No dial-up modem connection is necessary

Ø Offers fast connection set-up mechanism to offer a perception of being ‘always on’ or ‘always connected’

Ø Immediacy is one of the prime advantages of GPRS.

v GPRS Network Architecture

Ø GPRS uses the GSM architecture for voice

Ø To offer packet data services through GPRS, a new class of network nodes called GPRS support nodes (GSN) are introduced

Ø GSNs are responsible for the delivery and routing of data packets between the mobile stations and the external packet data networks (PDN)

Ø Two main GSNs are Serving GSN (SGSN) and Gateway GSN (GGSN)

 v GGSN

Ø GGSN acts as an interface between the GPRS backbone network and the external packet data networks and functions like a router in a LAN

Ø GGSN maintains routing information that is necessary to tunnel Protocol Data Units (PDUs) to the SGSNs that service particular mobile stations

Ø GGSNs convert the GPRS packets coming from the SGSN into the appropriate packet data protocol (PDP) format for the data networks like Internet or X.25

Ø GGSN stores the current SGSN address of the user and user’s profile in its location register while performing authentication and charging functions related to data transfer

v SGSN

 Ø SGSN is at the same hierarchical level as the MSC and so, whatever MSC does for voice, SGSN does for packet data

Ø SGSN’s tasks include packet switching, routing and transfer, mobility management, logical link management, authentication and charging functions

Ø SGSN processes registration of new mobile subscribers and keeps a record of their location inside a given service area

Ø Location register of the SGSN stores location information (like current cell, current VLR, etc.) and user profiles of all GPRS users registered with this SGSN

Ø SGSN sends queries to HLR to obtain profile data of GPRS subscribers

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GSM Architecture

     Cell are formed by the radio areas covered by a BTS (Base Transceiver Station).Several BTSs are controlled by one BSC.Traffic from the MS (Mobile Station) is routed through MSC. Calls originating from or terminating in a fixed network or other mobile networks is handled by the GMSC (Gateway MSC).
v Home Location Register (HLR) in GSM
  It contains the following information:

• Authentication information like International Mobile Subscriber Identity (IMSI).

• Identification information like name, address, etc. of the subscriber.

• Identification information like Mobile Subscriber ISDN (MSISDN) etc.

• Billing information like prepaid or postpaid.

• Operator selected denial of service to a subscriber.  Handling of supplementary services like for CFU (Call Forwarding Unconditional), CFB (Call  Forwarding Busy), CFNR (Call Forwarding Not Reachable) or CFNA (Call Forwarding Not Answered).

• Storage of SMS Service Center (SC) number in case the mobile is not connectable so that whenever the mobile is connectable, a paging signal is sent to the SCM.

• Information related to supplementary services for call routing. In GSM network, one can customize the personal profile to the extent that while the subscriber is roaming in a foreign PLMN, incoming calls can be barred. Also, outgoing international calls can be barred, etc.

• Some variable information like pointer to the VLR, location area of the subscriber, Power OFF status of the handset, etc.

    Entities in GSM

    The Mobile Station (MS) - This includes the Mobile Equipment (ME) and the Subscriber Identity Module (SIM).The Base Station Subsystem (BSS).

    This includes the Base Transceiver Station (BTS) and the Base Station Controller (BSC). The Network and Switching Subsystem (NSS) - This includes Mobile Switching Center (MSC), Home Location Register (HLR), Visitor Location Register (VLR), Equipment Identity Register (EIR), and the Authentication Center (AUC).

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WAP Evaluation

 
 Designed for access to Internet and advanced telephony services from mobile phones Pays intelligent sensitivity to the constraints of these devices like small display, limited keys on the keypad, no pointer device like mouse, etc.
  Evolution of WAP 

•  DoCoMo of Japan developed a language called compact Hyper Text Markup Language (C HTML) and a gateway which can be used for accessing the Internet.

•  Unwired Planet of USA developed a comprehensive framework including browser, gateway and markup language. The markup language was called Handheld Device Markup Language (HDML) and the protocol was called Handheld Device Transport Protocol (HDTP).

•  Ericsson of Europe developed Intelligent Terminal Transfer Protocol (ITTP) with the intent of making it easy for call control and adding services to mobile telephony platforms.

•  Ericsson, Motorola, Nokia, and Unwired Planet joined hands to launch the WAP Forum which is now known as Open Mobile Alliance.

•  The goal of WAP Forum was to produce a refined, license-free protocol, independent of the underlying air-link standard and it inherited its main characteristics and functionality from HDML, HDTP, Smart Messaging specification based on TTML, ITTP and NBS.

q Networks for WAP

 There are diffrent networks are used as given belows.There are used Network as GPRS,GSM and others.We can used that network for run our application.

o   All GSM modes.

o   GPRS.

o   CDMA IS-95 and cdma2000.

o   TDMA IS-136.

o   i-mode.

o   3G systems: IMT-2000, UMTS, W-CDMA and Wideband IS-95. 

 

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Bluetooth protocols

 Bluetooth have different protocols as core protocols,Replacement protocol, Telephony control protocol  and advance protocols.  The details are given belows.

1.   Bluetooth Core Protocols

Ø Baseband – enables physical RF link

Ø Link Manager Protocol (LMP) – manages devices in range, power modes, connections, duty cycles, etc.

Ø Logical Link Control and Adaptation Protocol (L2CAP)  segmentation and re-assembly of fragmented packets with their multiplexing

Ø Service Discovery Protocol (SDP) – Enables a device to join a piconet

2.   Cable Replacement Protocol

Ø Radio Frequency Communication (RFCOMM) - emulates RS-232 control and data signals over Bluetooth baseband protocol.

3.   Telephony Control Protocols

Ø Telephony Control Specification Binary (TCS BIN) – defines the call control signaling protocol and handles mobility management for groups of Bluetooth TCS devices

Ø Attention (AT) Commands - defines a set of commands by which a mobile phone can be used and controlled as a modem for fax and data transfers

4.   Adopted Protocols

Ø Point-to-Point Protocol (PPP) - means of taking IP packets to/from the PPP layer and placing them onto the LAN

Ø Transmission Control Protocol/Internet Protocol (TCP/IP) -used for communication across the Internet

Ø Object Exchange (OBEX) Protocol - session protocol to exchange objects and used to browse the contents of folders onremote devices

Ø Content Formats - used to exchange messages and notes and synchronize data amongst various devices.

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Bluetooth Introduction

Ø Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances (using short-wavelength radio transmissions in the ISM band from 2400–2480 MHz) from fixed and mobile devices, creating personal area networks (PANs) with high levels of security.

      Created by telecoms vendor Ericsson in 1994, it was originally conceived as a wireless alternative to RS-232 data cables. It can connect several devices, overcoming problems of synchronization.

v Bluetooth Protocol

Ø Uses the unlicensed 2.4 GHz ISM (Industrial Scientific and Medical) frequency band.

Ø 79 available channels spaced 1 MHz apart from 2.402 GHz to 2.480 GHz.

Ø Allows power levels starting from 1 mW (covering 10 centimetres) to 100mW (covering upto 100 meters) suitable for short device zone to personal area networks within a home.

Ø Supports both unicast (point-to-point) and multicast (point-to multipoint) connections.

Ø Bluetooth protocols are a collection of many inter-related protocols.

Ø Uses the master and slave relationship.

Ø Master and slaves together form a Piconet when master allows slaves to talk.

Ø Up to seven ‘slave’ devices can be set to communicate with a‘master’ in a Piconet.

Ø Scatternet is formed when several of piconets are linked together to form a larger network in an ad hoc manner.

Ø Scatternet is a topology where a device from one piconet also acts as a member of another piconet wherein a device being a master in one piconet can simultaneously be a slave in the other one.

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Downloading and Installing the JRE

Before you begin downloading and installing Eclipse, you have to make sure you have the Java Runtime Environment (JRE) downloaded and installed on your machine. Because Eclipse as an application was written in Java, it requires the JRE to run. If the JRE is not installed or is not detected, you will see the following error if you try to open the Eclipse environment:

• If you are downloading to a Microsoft Windows environment, when you see the notification in the following illustration, click Run to begin the installation of the JDK.

• During the installation process, you will be prompted to read and accept the License Agreement, shown next. After agreeing to the standard License Agreement and clicking.Next, you will be able to select your custom setup options

• To keep the process simple, and fairly standardized, you should accept the suggested packages by default everything is selected—and continue the installation by clicking Next. When the Installation Completed page appears, shown in the following illustration, click Finish and your installation should be completed

• Once you complete the Java JDK installation—and by default the JRE installation—you can begin to install Eclipse.

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Introduction to Android

v Introduction

What is Android?

Android is a software platform and operating system for mobile devices, based on the Linux kernel, developed by Google and later the Open Handset Alliance. It allows developers to write managed code in the Java language, controlling the device via Google-developed Java libraries. Applications written in C and other languages can be compiled to ARM native code and run, but this development path is not officially supported by Google.

The unveiling of the Android platform on 5 November 2007 was announced with the founding of the Open Handset Alliance, a consortium of 48 hardware, software, and telecom companies devoted to advancing open standards for mobile devices. Google released most of the Android code under the Apache license, a free-software and open source license.

What is The Open Handset Alliance?

Open Handset Alliance, is a consortium of several companies which include Google, HTC, Intel, Motorola, Qualcomm, T-Mobile, Sprint Nextel and NVIDIA, ... These companies which aim to develop technologies that will significantly lower the cost of developing and distributing mobile devices and services. The Android platform is the first step in this direction -- a fully integrated mobile "software stack" that consists of an operating system, middleware, user-friendly interface and applications.

License

Android is under version 2 of the Apache Software License (ASL). The Apache license allows manufacturers and mobile operators to innovate using the platform without the requirement to contribute those innovations back to the open source community.

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